Does "Fast" = "Detailed"?

"Every "fast" system that I have heard (as described by others) has been detailed, clear and without bloom. None have been what I'd consider warm and inviting. One or two have been cold, clinical and I could not listen for more than about an hour before getting a headache. Maybe I haven't yet heard the right "fast" system."

I regard my system as fast and detailed. I have no interest in a system that sounds as you describe. A good ribbon or electrotstatic system combined with tubes is fast and not at all cold or clynical. e.g.My Moscode and M/L CLS or Soundlabs with an Atma-Sphere amp.

fast = -LOG (square root of detail/ x-1)

If Bob has an amp playing Chicago at 100 Vus and Timmy's amp plays Boston at 5 VuS but has been warming up for an hour ....

The term "tight bass" is often used to describe a restriction in the drivers harmonics that increases sensitivity and detail.

I also think mdhoover is onto something... I've definitely heard some warm + fast systems; in fact I think my own system is warm and fast. Triodes (push-pull or single-ended) in general can sound this way, with great transient speed, but without the dryness of a "detailed" solid state amp. The trick for speed, I think, is high slew rate and good time-domain response for non-periodic signals... to capture that leading-edge. Bold (possibly false) claim: I think some "detailed"-sounding amps are really just injecting correlated noise from the power supply (from regulators, electrolytic caps, etc.), which give added illusion of texture and microdynamics (that dry clean sound). My amps sound less "detailed" but much faster since installing polypropylene caps to replace some electrolytic caps in the initial gain stages... I now suspect what I thought was real detail was nothing more than power supply noise, and good riddance to that!

Tvad makes some very good points about the potential for a fast system to become overly cold, clinical, and/or otherwise fatiguing.

Injecting fast into a system that is seriously lacking in one or more other categories can easily lead to an unbalanced or fatiguing presentation.

Therefore, careful attention (as always) must be placed on the synergy of the entire system to strike the least uncompromising balance for hours of enjoyment.

In other words, if you have a 'fast' system, then you'd better make sure that your mid-range is full and blooming and your bass is deep, tight, and well-defined, you are using proper line conditioning, and on it goes....

Here's a thread about fast amps that may be of interest including my post where I quote Peter Moncrief in his reviewing the top 25 solid state and top 25 tube amps back in 1998.

http://forum.audiogon.com/cgi-bin/fr.pl?aamps&1051879884&openflup&33&4#33

Moncrief describes his encounter with the McCormack DNA-2 LAE (Limited Anniversary Edition) amp and went on and on about its tremendous speed and labeled it the best solid state amp.

I owned the DNA-2 LAE amp but the DNA-2 Rev A amp was, among other things, faster. The Nuforce Ref 9 amps are, among other things, faster still. And the new Nuforce Ref 9 SE Special Edition amps are, among other things, significantly faster than the Ref 9s. The dynamics and level of detail is amazing with the SEs.

The SEs are by far the fastest amp I've yet encountered and by a pretty good margin. 6moons just released a review on the Nuforce SEs. It may interest you to see what they have to say about the level of detail, nuances, and dynamics of this amp. In fact, I'm starting to think that all of these other attributes has almost everything to do with speed.

-IMO
BTW, I ceased being just an enthusiast and became a dealer as a direct result of my first encounter with the Nuforce amps.